In the proposed 3-year supplemental project, a team of investigators from the State University of New York at Buffalo, Periodontal Disease Clinical Research Center will collaborate with established diabetics epidemiologists at the NIH, Southwestern Field Study Section in Phoenix, Arizona, to study relationships between the two diseases in a controlled population of Pima Indians with a high prevalence of non-insulin dependent diabetes mellitus (NIDDM). Studies will be done in the total population of the Gila River Indian Reservation to compare the prevalence and severity of periodontal diseases and other oral conditions in diabetic and non-diabetic subjects, and to correlate the findings with other complications of diabetics mellitus. In smaller selected groups of diabetics and non-diabetics, specific studies will be done to compare: a) peripheral blood phagocyte function (believed to be reduced in diabetic subjects); b) the composition of the subgingival bacterial flora in periodontal lesions; c) the responses to surgical and non-surgical periodontal therapy, including the effect of therapy on management of diabetes. The findings are expected to indicate that peridontal disease severity and prevalence are higher in NIDDM subjects, and can be correlated with reduced host blood phagocyte functions or with the presence of specific pathogenic bacteria. A better understanding of important host parasite interactions in periodontal disease as well as evaluation of periodontal disease as a complication aggravating diabetes are likely results of this study. Improved treatment of periodontal disease in diabetics and in the general population could result from this study, as well as better overall management of diabetic individuals. This proposed project takes advantage of the expertise of active research groups: The Periodontal Disease Clincal Research Center in Buffalo and the NIH, Southwestern Field Study Section in Phoenix and coordinates their efforts to study two important diseases in a community with an expected high prevalence of both diseases.